Iranian Journal of

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Backgrounds and Objectives: Hexavalent Chromium is an important contaminant in surface and ground waters and removal from contaminated water and waste water has received interest in recent years. Modified Zeolite with cationic surfactant can remove Cr(VI) from contaminant water. The aim of this research is investigation of Cr (VI) removal from aqueous solutions and its effective parameters by using Modified Zeolite with cationic surfactant.
Materials and Methods:In this research the efficiency Of Cr(VI) removal and impact of the important parameters including adsorbent dose, pH and contact time in the batch system was studied.
Results:The results of this research showed that SMZ can remove more than 90 & Cr(VI) in the concentration 0.1-1.25 mg/l with optimum dose 0.3 gr and pH=6 120 minute in contact time.
Conclusion: Modified natural zeolite have significant potential inCr(VI) removal fromcontaminated water.Maximumpercent removal ofCr(VI)was in the pH=6 and 120minute contact time.Adsorption data in the equilibrium was fitted with Langmuir isotherm. Separation factor was between 0 and 1 that indicates the favorable condition for Cr(VI) adsorption on the SMZ.

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Background and objective: Metal pollution has always been a major cause of contamination of environment and is considered as a major concern for food health. Worldwide, sturgeons are an important source of food and income. In this study, the human health risk due to consumption of caviar and muscle of Persian sturgeon (Acipenser persicus) were evaluated by measuring the concentrations of cadmium, nickel, vanadium and zinc in caviar and muscle samples. Material and Methods: A total number of 24 samples of Persian sturgeon were collected from two important sturgeon fishery zones in Guilan and Mazandaran Provinces and were stored at −20°C until chemical analysis. About one gram of each sample dried was added to 10 ml of concentrated (65%) supra-pure HNO3 (Merck, Darmstadt, Germany) in a Teflon PTFE tube and then it was incubated for 1 h at 40 °C in a hot block digester, followed by heating at 140 °C for 3 h. The samples digested were diluted to a measured volume using double deionized water. Samples were filtered through Whatman No. 1 filter paper, and the filtrate was stored until metal determination. Results: Mean Cd, Ni, V and Zn concentrations in muscle tissues were 0.005 ± 0.002, 0.06 ± 0.03, 0.13 ± 0.04 and 7.49 ± 3.07 µg/g wet weight basis respectively. The mean Cd, Ni, V and Zn concentrations in caviar samples were 0.007 ± 0.006, 0.09 ± 0.07, 0.12 ± 0.15 and 21.23 ± 5.75 µg/g wet weight basis respectively. Conculation: The mean concentrations of Zn, Cd and V in caviar and muscle samples were less than the permissible limits proposed by the United Kingdom's Ministry of Agriculture, Fisheries and Food (MAFF 2000) and World Health Organization (W.H.O.). The guidelines for Cd, V and Zn are 0.2, 0.5 and 50 µg/g wet weight respectively. Therefore, the measured concentrations for these particular metals are below the published guidelines, and the levels would appear not to constitute any threat to the human population that may consume sturgeon or caviar obtained from these study locations.

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Background and Objectives: bisphenol A and nonylphenol are xenoestrogen materials used as a monomer of plastics in widely volume in the production of plastic materials especially mineral water bottles and disposable plastic containers. In this study, we investigated the potential of migration of bisphenol A and nonylphenol from disposable plastic containers into water at different temperatures and also from mineral water into water at different temperatures. Materials and Methods: We conducted bisphenol A and nonylphenol extraction from each sample through liquid-liquid extraction. For identification and quantitative determination of bisphnol A and nonylphenol, we used gas chromatography equipped with mass detector, and for quantitative determination of these two compounds, we used high-performance liquid chromatography equipped with fluorescence detector. Results: We found that increasing temperature increased significantly the rate of migration of these two compounds in the water. Moreover, it was revealed that only the presence of bisphenol A in water of mineral water bottles was detected and the increase in temperature also increases the rate of migration bisphenol A into water. Conclusion: In general, results of this study showed that improper storage of mineral water bottles and also use of disposable plastic containers for hot drinks would result in increasing consumer exposure to these compounds.

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